I have a brand new yta24V48 Husqvarna mower. It appears to slip uphill. I have been told the housing is sealed so fluid cannot be checked. What are your suggestions.

Question edited for clarity.

Shown on Page 20 of the manual.

https://www.manualowl.com/m/Husqvarna/YTA24V48/Manual/493664?page=20

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I believe this unit has a K46 transaxle. Hydrostat fluid level check and fill procedure may be found in the axle seal replacement guide.

https://www.tufftorqservices.com/instance1EnvEEdefault/FlatHTML/TechInfo/docs/repair/K46_T40_TLT200Axle_Seal_REPLACEMENT.pdf

See procedure starting at page 7. Service assumes the transaxle has been removed from unit.

Replace the drive belt. The hydraulic drive is sealed.

if this is a hydrostatic chang fluid and filter see if it wont improve

If you are lucky it could be a belt slipping, so a new belt will cure this however as this happens when the machine warms up it could well be a hydro problem, as the oil in the hydro heats up it becomes more viscous so if there is wear in the hyro it will leak internally causing slow running.

A hydrostatic transaxle could be low on fluid, or have leaky pump or motor. Check the fluid level. If it is not hydro, check belt from the engine to the transaxle for tightness or slippage.

those fluid drive transmissions fail on quite a few brands as they all use the same ones....replace the trans...they are expensive but still cheaper than a new mower.

it has a leak from the head gasket,ive done many with the same problem.pop the head off and change the gasket,also check the rings ect while apart

u can change belt yourself need belt size and have to remove cutting deck but check belt tension first if loose with brake off belt stretched out and slipping needs replacement

My lawnmower done the same thing right after we purchased it. They had to replace the whole motor